Fixed bug noted in previous commit by adding a UserData model to store AWS username parameter used for create_instance and other AWS functions.  Renamed index_bs.html to index.html, overwriting previous index.html.

Fixed bug noted in previous commit.  Added UserData model to store AWS
Username parameter used for create_instance.  This allows a Google
Account to be used, and for each Google Account, a separate AWS
username can be set by the administrator.